Swiss 'janitor' satellite to sweep up space junk

Swiss scientists plan to launch a shoebox-sized satellite with jellyfish-like tentacles to sweep up space junk as early as 2016.

The $11 million satellite, called CleanSpace One, would chase down space junk and drag it out of orbit, burning up during atmospheric re-entry in the process. Swiss space scientists hope this will be the first of a fleet of "janitor" satellites.

"We want to offer and sell a whole family of ready-made systems, designed as sustainably as possible, that are able to de-orbit several different kinds of satellites," said Volker Gass, director of the Swiss Space Center at the Federal Polytechnic School of Lausanne.

The cloud of debris from dead or discarded spacecraft circling the Earth poses a serious threat to active satellites, like those used for GPS or telecommunications, as well as to the six astronauts aboard the International Space Station. NASA estimates that more than 6000 tonnes of space junk zip around the planet at speeds of about 28,000 kilometres per hour. Even a paint chip can do damage at such speeds.

The danger was highlighted in 2009 when two intact spacecraft, the Russian Cosmos satellite and the US communications satellite Iridium-33, collided head-on, leaving behind a trail of hundreds of pieces of debris. It came up again earlier this year, when the space station had to shift to a higher orbit to dodge a piece of shrapnel from a dead Chinese satellite that was deliberately destroyed in 2007.

Some scientists fear that the space junk problem is reaching a critical tipping point, where the amount of debris is growing faster than individual pieces can fall out of the sky. Scientists have suggested several novel ways to cope, including a net that could guide debris downward to its destruction, or equipping future satellites with solar sails so they can de-orbit themselves when their working lives are over.

CleanSpace One may be the first dedicated clean-up crew to get off the ground. The spacecraft is designed to rendezvous with one of two shoebox-sized dead satellites – either SwissCube, which launched in 2009, or TIsat, which launched in 2010.

Once it has caught up with its quarry, CleanSpace One will deploy grippers inspired by jellyfish or sea anemones to embrace the spinning target. Then it will power its engines to steer itself on a suicide dive into Earth's atmosphere.